The Association Between Low‐Density Lipoprotein Cholesterol and Incident Atherosclerotic Cardiovascular Disease in Older Adults: Results From the National Institutes of Health Pooled Cohorts

BACKGROUND/OBJECTIVES: Elevated low-density lipoprotein cholesterol (LDL-C) in early adulthood is associated with increased risk of atherosclerotic cardiovascular disease (ASCVD). The strength of the association between LDL-C and ASCVD among older adults, however, is less understood. DESIGN: We examined individual-level cohort data from the National Institutes of Health Pooled Cohorts (Framingham Study, Framingham Offspring Study, Multi-Ethnic Study of Atherosclerosis, and Cardiovascular Health Study), which prospectively measured CVD risk factors and incident disease. SETTING: Prospective cohort study. PARTICIPANTS: Adults, aged 75 years or older, free of ASCVD. MEASUREMENTS: We evaluated the associations between LDL-C and incident ASCVD (stroke, myocardial infarction, and cardiovascular death) in unadjusted analysis and in multivariable-adjusted Cox proportional hazards models. We assessed 5-year Kaplan-Meier ASCVD event rates in patients with and without hyperlipidemia (LDL-C ≥130 mg/dL or on lipid-lowering medications), stratified by the number of other risk factors, including smoking, diabetes, and hypertension. RESULTS: We included 2667 adults, aged 75 years or older (59% female), free of ASCVD; median age was 78 years, with median LDL-C of 117 mg/dL. In both unadjusted and adjusted analyses, there was no association between LDL-C and ASCVD (adjusted hazard ratio = 1.022; 95% confidence interval = 0.998-1.046; P = .07). Among adults without other risk factors (free of smoking, diabetes, and hypertension), event rates were similar between those with and without hyperlipidemia (Kaplan-Meier rates = 5.8% and 7.0%, respectively). Among adults with one or two or more other risk factors, the presence of hyperlipidemia was also not associated with 5-year CVD event rates (Kaplan-Meier rates = 12.8% vs 15.0% [P = .44] for one other risk factor and 21.9% vs 24.0% [P = .59] for two or more other risk factors). CONCLUSION: Among a well-characterized cohort, LDL-C was not associated with CVD risk among adults aged 75 years or older, even in the presence of other risk factors. J Am Geriatr Soc 67:2560-2567, 2019.